The Blob Spreads! What is it!

What the heck is this thing growing here. It was just a little dot of white at the end of the rock when I put this frag piece here. Now its grown and attached the frag rock to the main rock. And its spreading through the polyps as you can see here. There are similar small dots of the same thing growing further along on the same rock.

 

hmm sponge maybe?

 

I was thinking the same thing, even though your description makes it seem invasive, it doesnt look like your polyps are bothered too much by it.

 

Ive seen a type of worm that created a slime coating to make burrows of a sort... I had one make a good size den in a rock crevice... Unfortunate, I do not recall the name and I could be wrong all together... I hope someone chimes in with the answer

 

After taking a second look of it, it seems very smooth... So maybe im wrong :/

 

Better description perhaps::::

It is smooth. Its slippery....but not slimy. It was just a pin head sized ball at first.....just thought it was a new polyp growth! It is not gelatinous to the touch....its quite firm and doesn't depress even when poked or prodded at. It's moving/spreading out wards from the shade into the more lit area of the frag rock and up out of the crevice on the main rock....so its looking for more light...it seems. And it is maneuvering through the polyps and doesn't yet seem to be harming them. But it is spreading quite fast now!

 

Looks like an encrusting sponge of some sort.

 

Is it going to be okay for his polyps or is it going to overcome them?

 

black encrusting sponges will override polyps. I don't know about that species. Maybe keep an eye on it.

 

HMMM.....encrusting! Don't like the sound of that!